ENS 45876
ENS Event | |
|---|---|
12:30 Mar 15, 2010 | |
| Title | Radiation Underdose at Prescribed Location |
| Event Description | The following information below is a summary of a facsimile provided by the State of Louisiana Department of Environmental Quality concerning a reported medical event:
A medical event occurred involving a patient under treatment for adenocarcinoma of the prostate gland. The patient involved received a prostate brachytherapy implant on March 12, 2010, using radioactive iodine-125 seeds [95 seeds of I-125 were implanted at 0.322 mCi/seed]. The radiation oncologist with the assistance of the urologist inserted the needles through the appropriate holes in the needle template. During the procedure, the radiation oncologist used the ultrasound to guide the needle placement. However, the radiation oncologist and ultrasound technologist had difficulty seeing the balloon location (indicating the prostate base) clearly on the sagittal view of the ultrasound during the dispensing of the seeds from the needles. It was felt that it was possible that the patient may have moved during the procedure which may have caused the balloon and ultimately the base plane to have shifted. A variance was suspected by the radiation oncologist after reviewing the post implant seed count x-ray. The patient was called to return for an early post-implant CT on March 22, 2010 to confirm the implanted seed locations. Using these images, a treatment plan was constructed using the treatment planning system's post-plan software. Based on this postoperative plan, it has been estimated that the entire implanted volume was shifted approximately 3.0-cm inferiorly, resulting in D90% of 12.88 Gy (dose that covers 90% of the prostate volume outlined on the post implant CT images). The prescription dose was 145.0 Gy. The post-implant planning results were referred to the Radiation Safety Committee (RSC) for review. After review, the RSC decided to interpret the implant as a medical event. This decision was made based on the fact that the V100 (volume of the prostate that received 100% of the prescribed dose) was less than 50% and the event classification was felt to be that of a wrong site. The information provided to the patient was that a treatment delivery inaccuracy occurred on March 15, 2010. The radiation oncologist explained to the patient that the dose delivered was not as planned and that supplemental treatment is recommended to treat his prostate cancer. A waiting period is recommended to allow the sources to decay and to determine any possible complications. Louisiana Report # LA100003 A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient. |
| Where | |
|---|---|
| Mary Bird Perkins Cancer Center Baton Rouge, Louisiana (NRC Region 4) | |
| License number: | La-2651-L01 |
| Organization: | Louisiana Radiation Protection Div |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+1031.57 h42.982 days <br />6.14 weeks <br />1.413 months <br />) | |
| Opened: | Scott Blackwell 12:04 Apr 27, 2010 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Apr 27, 2010 |
| 45876 - NRC Website | |
Mary Bird Perkins Cancer Center with Agreement State | |
WEEKMONTHYEARENS 458762010-03-15T12:30:00015 March 2010 12:30:00
[Table view]Agreement State Radiation Underdose at Prescribed Location ENS 447882008-12-23T06:00:00023 December 2008 06:00:00 Agreement State Agreement State - Medical Misadministration ENS 422632005-11-22T06:00:00022 November 2005 06:00:00 Agreement State Agreement State Report - Medical Event 2010-03-15T12:30:00 | |